OREANDA-NEWS. November 26, 2012. Cogent Power, a wholly owned subsidiary of Tata Steel, has developed a range of new electrical steel grades suitable for hybrid (HEV) and electric vehicle (EV) drive motor applications.

Electrical steels are usually developed to provide specific electromagnetic properties as defined in European and international industry standards. However, these standards do not offer any specification in terms of mechanical characteristics. There is a growing trend for significantly higher rotating speeds in motors to achieve improved power densities and material strength is therefore an increasingly critical factor.

A typical industrial induction motor might rotate at 3,000 rpm, while many drive motors for HEV and EV applications are designed for a rotating speed of 10,000 rpm, and in some cases, even higher.

To help meet the demanding mechanical requirements of these next-generation high-speed rotating machines, Cogent Power can now offer three non-grain oriented (NGO) electrical steel grades (M330-35HT, M330-35HS and M250-35HS) in 0.35 mm gauge with guarantees of both electromagnetic and mechanical properties. In addition, Cogent Power is also now offering a unique 0.50mm NO50 NGO grade, which has been specifically developed for cost-effective use at elevated frequencies above 50 Hz.

Magnus Lindenmo, technical development manager at Cogent Power’s Surahammar Bruks business in Sweden, said, “We are committed to providing our customers with a wide range of high-performance and high-efficiency electrical steels and recognise that for our customers developing low-carbon vehicles, mechanical performance is just as critical as electromagnetic performance.’’

Cogent Power's general manager, Mark Cichuta said, “I am delighted that we have been able to expand our electrical steel portfolio in this way. This new product development shows the kind of benefit we can bring to our customers now we have full control over our production processes from raw materials to finished products.”

The Surahammar plant has since 2007 been supplied with hot rolled NGO electrical sheet primarily from Tata Steel’s IJmuiden works in the Netherlands.